KR20120017007A - Printing head, printer, and method for controlling a printer - Google Patents

Abstract

PURPOSE: A print head, a printer and a control method of the printer are provided to peel off the recording media in a high success rate because the print heat is transferred even in the state that the record media are attached. CONSTITUTION: A print head(5) comprises a head main body unit(8) and a support mechanism. The head main body unit comprises a printing unit(8a) printing the recording media. The head main body unit faces a platen roller(4) sending back the recording media. The support mechanism supports the head main body unit in the platen roller. The support mechanism transfers the head main body unit in a direction of changing the position of the head body unit in the sate of pressurizing the head main body unit in the platen roller.

Description

PRINTTING HEAD, PRINTER, AND METHOD FOR CONTROLLING A PRINTER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support mechanism of a print head, a printer, and a control method of a printer. In particular, the platen roller is rotationally driven with a recording medium sandwiched between the print head and the platen roller to be pressed. A printer having a print head support mechanism, a print head support mechanism, and a printer control method in a printer for printing while transporting a recording medium.

In a printer in which a platen roller is disposed to face the print head and is printed while the recording medium is sandwiched between the print head and the platen roller, the printer is placed in a standby state with the recording medium sandwiched between the print head and the platen roller. It may enter, and a long time may elapse with the recording medium pressurized by the printhead. When such a printer prints on a recording medium that is easy to attach when pressurized, such as a recording medium coated on a printing surface, the recording medium may adhere to the print head when left in a standby state for a long time.

Patent Document 1 discloses a thermal printer that performs an operation for releasing the adhesion caused by the pressurization state of a recording medium (label) to a print head (thermal head) for a long time. In the thermal printer, when the printing standby state is continued for a predetermined time or more, control is performed to rotate the platen roller in the forward and reverse directions while the print head is pressed against the platen roller side, and the recording attached to the print head is executed. The medium is repeatedly pulled back and forth along the conveyance direction to peel it off.

Japanese Unexamined Patent Publication No. 2006-334858

In patent document 1, it is the structure which peels a recording medium from a printing head by a shearing force, moving a recording medium to a front-back direction in the state which stopped and pressed the printhead to the platen roller side. However, when the recording medium is strongly attached to the print head, the shearing force required to peel it off is the rotational driving force of the platen roller by a general motor and the ability to transfer the force due to friction between the platen roller and the recording medium. The platen roller may slip, causing the platen roller to slip and may not be able to convey the recording medium. Therefore, there is a possibility that the recording medium cannot be stretched with a sufficient force, so that the adhesion cannot be eliminated.

An object of the present invention is to propose a printer capable of easily peeling a recording medium even when the recording medium is strongly attached to the print head, a support mechanism of the print head for this, and a control method of the printer.

MEANS TO SOLVE THE PROBLEM In order to solve the said subject, the printhead support mechanism of this invention has the printing part which prints a recording medium, the head main body part which opposes the platen roller which conveys the said recording medium, and the said head main body part is the said plate And a support mechanism for moving the head main body in a direction of changing the position of contact with the platen roller while pressing the head main body to the platen roller while supporting the platen roller. have.

According to the present invention, when the recording medium is attached to the print head, the present invention pressurizes the portion (the portion pressed by the platen roller in the head main body portion) by the platen roller. Can be opened from. For example, by applying a force toward the movable direction of the print head, the recording medium and the print head can be moved together, and the portion to which the recording medium is attached can be released from the pressing position by the platen roller. . When released from pressurization, it becomes possible to move the recording medium in the direction of peeling the recording medium from the print head. When the recording medium is peeled off, the recording medium is peeled off with a smaller force than when peeling off only by the shearing force. Further, by moving the print head in a state where the recording medium is attached, the force to release the recording medium from the print head may be exerted by loosening the recording medium or moving it to a position away from the normal conveyance path. Therefore, the attachment of the recording medium can be easily eliminated with a high success rate.

It is preferable to perform the movement of the head main body portion in the support mechanism by rotation in the first direction of the platen roller or rotation in a second direction opposite to the first direction. In this way, the attachment removal operation | movement operation can be performed by the conveyance operation | movement by the existing platen roller, and it is not necessary to provide a new drive source for moving a print head. Therefore, there is no need to complicate the device configuration, and the attachment removal can be realized at low cost. In addition, in order to convey the recording medium along the conveying direction of the normal recording medium, the recording medium can be loosened on the upstream side or the downstream side of the conveying direction with respect to the print head to exert a force to exfoliate the recording medium. .

The support mechanism has a rotation support surface in contact with a rotation axis parallel to the rotation axis of the platen roller, and a guide surface extending to the position side in contact with the platen roller of the head main body part continuously with the rotation support surface, By the contact between the head main body portion and the platen roller, the rotation support surface or the guide surface is pressed against the rotation shaft so that the rotation shaft relatively moves along the guide surface to contact the platen roller of the head body portion. It is good also as a structure which moves the position to contact with the said platen roller of the said head main-body part by rotating the said support mechanism on the said rotation support surface. Thus, by providing the guide surface in the print head and making the rotating shaft pressed against this slideable, it becomes possible to move the print head in parallel in the direction which moves a press part a little while supporting a printing head by a rotating shaft.

In the support mechanism of the print head, the guide surface may be inclined in the direction of stretching to the back side of the head body portion as it faces the rotational support surface side. In this way, the print head can be retracted to the back side of the head main body part by moving the rotational axis along the guide surface and moving the pressing position. Therefore, the portion to which the recording medium adheres moves to a position deviated from the conveying path as it moves away from the press position, whereby the rising angle with respect to the attaching surface of the recording medium increases, and the recording medium is moved from the head surface. The force to exfoliate is greater. Therefore, it is possible to quickly eliminate the attachment of the recording medium.

Next, a print head including a platen roller for conveying the recording medium, a head main body portion opposed to the platen roller with a printing portion for printing the recording medium, and pressing the print head against the platen roller side. Pressurizing means and the head main body portion to support the platen roller, and at the same time changing the position of contact with the platen roller of the head main body part while pressing the head main body portion to the platen roller; It has a support mechanism which moves a head main-body part, It is characterized by the above-mentioned.

Moreover, the printer of this invention has a conveyance path which conveys the said recording medium to the position which the said platen roller and the said head main body part contact, and the said predetermined head main body part moves with respect to the said platen roller in the said conveyance path | route. It may further have a guide member located on the same side as the direction to guide the recording medium. In this way, when the guide member is provided on the side where the print head moves to restrict the movement path of the recording medium, the recording medium cannot be bent in a short section from the guide member to the print head, so that The granular angle reliably increases. Therefore, the force to exfoliate actively can be exerted.

Next, the control method of the printer of the present invention receives an operation instruction involving conveyance of a recording medium, measures a period of print waiting until the operation instruction is received, and the measured period of print wait is And when the head body portion of the print head is pressed against the platen roller when the predetermined time period is exceeded, the head body portion is moved in a direction of changing the position of contact with the platen roller. Here, the printing standby is a state where the recording medium is stopped at a position where the head main body portion and the platen roller come into contact with each other.

According to the present invention, when the recording medium is attached to the print head, the print head can be moved to open a portion to which the recording medium is attached from being pressed by the platen roller. At the portion open from pressurization, it becomes possible to move the recording medium in the direction of peeling the recording medium from the print head. Further, by moving the print head in a state where the recording medium is attached, the recording medium can be loosened or moved to a position away from the normal conveyance path, thereby exerting a force to peel the recording medium from the print head. Therefore, the attachment of the recording medium can be easily eliminated with a high success rate.

BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing which shows the cross-sectional structure of the principal part of the thermal printer of this embodiment.
2 is a perspective view of a thermal head,
3 is an explanatory diagram showing an attachment release operation of a print head;
4 is a flowchart of an attachment release operation of a print head.

EMBODIMENT OF THE INVENTION Below, with reference to drawings, the thermal printer which is embodiment of the printhead support mechanism to which this invention is applied, and the printer provided with this is demonstrated.

(The overall configuration of the printer)

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the cross-sectional structure of the principal part of the thermal printer of this embodiment. The thermal printer 1 (printer) prints the long recording paper 2 (recording medium) while conveying it along the conveyance path 3 in the printer, and arranges it at a predetermined position on the conveyance path 3. Platen roller 4 and thermal head 5 (print head) disposed opposite to platen roller 4 are provided. A paper inlet 1a is provided on the lower surface of the device of the thermal printer 1, and the recording paper 2 supplied into the apparatus through the paper inlet 1a is disposed between the thermal head 5 and the platen roller 4. It is loaded to pass. Above the thermal head 5 and the platen roller 4, a paper outlet 1b is provided, from which the printed recording paper 2 is discharged to the outside. As the recording paper 2, a long thermal paper, a label on which a thermal paper is labeled, and the like can be used.

The paper guide member 6 (guide member) for guiding the recording paper 2 is provided in the upstream conveyance path portion from the paper inlet 1a to the thermal head 5 and the platen roller 4. In the present embodiment, the paper is slightly disposed on the platen roller 4 side (left side in FIG. 1) rather than just under the insertion position P of the recording paper 2 by the thermal head 5 and the platen roller 4. The inlet 1a is arrange | positioned. Therefore, the guide path by the paper guide member 6 extends inclined toward the insertion position P located in the upper right direction with respect to the paper inlet 1a. The recording sheet 2 passing through the sheet guide member 6 is turned upward across the platen roller 4.

The rotation drive force of the conveying motor 7 is transmitted to the platen roller 4 via transmission mechanisms, such as a gear which is not shown in figure. When the platen roller 4 rotates in the forward direction (the direction of the arrow A in Fig. 1), the recording paper 2 is conveyed in the forward direction toward the paper outlet 1b in accordance with this rotation. In addition, when the platen roller 4 rotates in the reverse direction (the direction opposite to the arrow A), the recording paper 2 is conveyed in the opposite direction toward the paper inlet 1a. Here, in this specification, the conveyance direction (the conveyance direction of the recording sheet 2 at the time of printing: arrow B direction in FIG. 1) which conveys the recording sheet 2 toward the paper exit 1b is made into a reference conveyance direction. .

(Print head and its supporting structure)

2 is a perspective view of a thermal head. As shown in FIG. 1 and FIG. 2, the thermal head 5 is in the up-down direction on the head main body 8 facing the platen roller 4 side and the back side of the head main body 8. An extending support frame 9 is provided. In the part near the upper end of the head main-body part 8, the heat generating part 8a for heating the recording paper 2 and performing printing is provided. When printing by the thermal head 5, the part of the heat generating part 8a in the head main-body part 8 faces the platen roller 4 in front, and the heat generating part 8a and the platen roller ( 4) A state in which the recording sheet 2 is sandwiched between them is formed.

The support frame 9 has the notch 10 formed in the part which extends toward the downward direction of the head main-body part 8, ie, the part which extends toward the upstream side of a reference conveyance direction rather than the heat generating part 8a. Equipped. This cutout part 10 is opened toward the side in which the conveyance path 3 is provided, and is close to the press part by the platen roller 4 in the head main-body part 8, ie, the heat generating part ( The side closer to 8a is shallower, and the side farther from the heat generating portion 8a is deep. A straight guide surface 11 is provided at the bottom of the cutout 10, and a curved rotary support surface 12 is continuously formed at the lower end of the guide surface 11. Here, the guide surface 11 inclines with respect to the head main body part 8, and the inclination direction extends toward the rotation support surface 12 side (lower side of FIG. 1), and the head main body part 8 It is a direction to retreat to the back side (right side of FIG. 1) of.

When the thermal head 5 is disposed so as to replace the head main body 8 with the platen roller 4, the rotation shaft 13 supported by the main body frame of the thermal printer 1 opens the cutout 10. Face to face. The rotating shaft 13 is provided in parallel with the rotating axis of the platen roller 4. The thermal head 5 is pressed to the platen roller 4 side by the head press spring 14 (pressure member) provided in the back side of the head main-body part 8. The head main body 8 is pressed by the platen roller 4 by the pressing force of the head pressurizing spring 14, and the state in which the rotating shaft 13 is pressed on the inner side of the notch 10 is formed.

As shown in FIG. 1, when the heat generating part 8a faces the platen roller 4 in front, the rotating shaft 13 is located in the lower end of the notch 10, and is inscribed on the rotating support surface 12. As shown in FIG. Becomes At this time, it is possible to rotate the thermal head 5 by slidingly contacting the rotary support surface 12 with the outer peripheral surface of the rotating shaft 13. That is, the state in which the thermal head 5 is rotatably supported about the rotating shaft 13 is formed.

Moreover, when the thermal head 5 is tensioned to the upstream side or the downstream side (upward direction or downward direction of FIG. 1) of the reference | standard conveyance direction of the recording paper 2, the rotating shaft 13 may rotate the guide surface 11. As shown in FIG. By sliding along, the thermal head 5 is guided and moved in the direction along the tension direction, supporting the thermal head 5 against the pressing force of the head press spring 14. That is, the thermal head 5 is provided with the rotating shaft 13 and the guide surface 11 with respect to the rotating shaft 13 within the operation range at the time of the sliding shaft 13 sliding along the guide surface 11. It is supported so that relative movement is possible.

(Removal of Attachment of Recording Paper)

Fig. 3 is an explanatory diagram showing the attachment release operation of the recording paper in the print head. Fig. 3A shows the state where the print head and the recording paper adhere, and Fig. 3B shows the movement of the print head. 3C shows a state in which the print head is returned to its original position after the attachment is released.

In the present embodiment, when printing on the recording paper 2, as shown in Figs. 1 and 3A, the thermal head 5 is positioned at the position where the rotary shaft 13 is inscribed with the rotary support surface 12. ) Is positioned, and the heat generating portion 8a is opposed to the front surface of the platen roller 4 that protrudes most toward the thermal head 5 side. Then, by the head press spring 14, the thermal head 5 is pressed in the direction of turning to the platen roller 4 side with the rotation shaft 13 as the center, and the heat generating portion 8a is pressed against the platen roller 4. Is pressed toward the platen roller 4 side with the recording sheet 2 sandwiched between the pads. In the print standby state of the thermal printer 1, this state is maintained. For this reason, when a printing standby state continues for a long time, the recording paper 2 pressed against the to-be-pressed area | region C centering on the heat generating part 8a is pressurized by the pressing force from the platen roller 4 side. The state attached to the area | region C is formed.

4 is a flowchart of an attach dismantling operation. When the control unit of the thermal printer 1 receives an execution command of an operation involving conveyance of the recording paper 2 such as a print start command, the waiting time T at that time (continued time of the print waiting state) It is determined whether or not the preset limit time T0 is exceeded (step S1). And if the print wait state continues beyond the limit time T0 (step S1: YES), it will transfer to step S2. On the other hand, when the waiting time T is within the limit time T0 (step S1: NO), steps S2 to S3 are omitted and the process proceeds to step S4 to start an instructed operation such as a print operation.

In step S2, the control unit of the thermal printer 1 executes a conveying operation for conveying the appropriate amount of the recording sheet 2 in a direction opposite to the reference conveying direction. For example, in order to reversely convey the recording paper 2 by a conveyance amount corresponding to a length of 24 dots of a printing dot formed by the thermal head 5, the platen roller 4 is conveyed by an opposite amount of 24 dots. Reverse the rotation by the amount equivalent to. In this case, the conveyance force toward the upstream side of the reference | standard conveyance direction acts on the part of the recording paper 2 adhering to the to-be-pressed area | region C, and the thermal head 5 carries out the reference conveyance direction via the recording paper 2. Is pulled upstream.

Since the rotating shaft 13 can slide along the guide surface 11, the thermal head 5 is in the mounting state which can be moved relatively with respect to the platen roller 4. Therefore, when the thermal head 5 is pulled upstream through the recording paper 2 attached to the pressurized region C, the thermal head 5 slides the rotation shaft 13 along the guide surface 11 and is generally in the same direction as the tension direction. Move. Thus, when the thermal head 5 is relatively moved with respect to the platen roller 4, a pressurized position will shift | deviate toward the downstream side of a reference conveyance direction from the to-be-pressed area | region C. As shown in FIG. As shown in FIG. 3B, the opposite amount of transfer of step S2 is such that the thermal head 5 is moved until the pressurized region C is completely out of the pressing position by the platen roller 4. Possible conveyed amount. Therefore, by performing step S2, the pressurized region C moves to the upstream side and is completely opened from pressurization.

In addition, when the thermal head 5 moves in step S2, the upper surface of the head main body 8 is pressed against the platen roller 4 and the rotating shaft 13 pressed against the guide surface 11. The movement is regulated by By this restriction, the thermal head 5 does not move in the movement direction which is exactly the same as the tensile force, but in the direction in which the upper part is inclined toward the platen roller 4 as a whole (counterclockwise rotation in FIG. 3 (b)). While slightly turning, it moves in the direction of descending downward on the right inclination parallel to the guide surface 11. Accordingly, the pressurized region C moves to a position outside the normal conveyance path 3, and the recording paper 2 attached to the pressurized region C also moves to a position outside the normal conveyance path 3. do. Thereby, in the upstream side of the to-be-pressed area | region C, it becomes an attitude to stand up so that the recording paper 2 may make | form a predetermined granular angle E from a head surface, and the recording paper 2 is moved from the to-be-pressed area C. ) Exerts a force (force acting in the F direction of FIG. 3B). Therefore, the recording paper 2 is peeled more easily than the peeling method by the conventional shearing force.

Moreover, in this embodiment, the paper guide member 6 extended to the front of the platen roller 4 is provided in the conveyance path | route 3 of the upstream, and guides the recording paper 2. As shown in FIG. Therefore, when the to-be-pressed area C moves to the position beyond the normal conveyance path 3, the recording paper 2 is short in the section from the paper guide member 6 to the to-be-pressed area C. In FIG.3 (b), it will be in the state along the bending path D shown with the broken line. This bending state is a bending state in which the granular angle E is large in a portion where the recording paper 2 stands up from the head surface, and is a bending state in which a force to peel the recording paper 2 from the pressurized region C is large. . That is, by forming such a state, the recording paper 2 can be peeled off at a high success rate. Since the standing angle E of the recording paper 2 gradually increases in the process of moving the thermal head 5 from the position of FIG. 3A to the position of FIG. 3B, the recording paper 2 is increased. The force to peel off gradually increases. Therefore, the recording paper 2 can be peeled smoothly.

In addition, when the paper guide member 6 is omitted, since the path of the recording paper 2 is not restricted on the upstream side, it becomes possible to bend the recording paper 2 largely and gently. Therefore, the granular angle E of the recording paper 2 does not become very large. However, since the force to peel off acts, it can peel more easily than the method of peeling by the conventional shearing force. Further, even when the moving destination of the pressurized region C does not greatly deviate from the normal conveyance path 3, since the warp of the recording paper 2 occurs due to the reverse conveyance, it is not as large as in the above case, Power functions. Therefore, the recording paper 2 can be peeled off more easily than the conventional shearing method alone.

After the operation | movement of step S2 is completed, the control part of the thermal printer 1 transfers to step S3, and conveys a recording paper in the forward direction (reference conveyance direction) by the conveyance amount equal to the reverse conveyance amount of step S2. For example, the platen roller 4 is rotated forward by a rotational amount corresponding to a 24-dot forward feed. Thereby, as shown in FIG.3 (c), the recording paper 2 returns to the position before standby, and the printing start position of the recording paper 2 is the insertion position P by the platen roller 4 Is positioned on. Moreover, the thermal head 5 pressurized by the recording paper 2 conveyed in the reference conveyance direction is pulled downstream with the recording paper 2, and moves in the reverse direction the movement path moved to step S2, so that the heat generating portion 8a. ) Is formed between the platen roller 4 and the recording paper 2. In addition, at this time, since the guide surface 11 is inclined, the pressing force of the head press spring 14 acts as a force for sliding the entire thermal head 5 to the upper left inclined along the direction of the guide surface 11. do. When the thermal head 5 returns by the above, it transfers to step S4 and starts the operation | movement which was indicated such as a printing operation.

As described above, the thermal printer 1 of the present embodiment exerts a force in a direction in which the recording paper 2 attached to the head main body 8 is released from pressure by the platen roller 4 to be peeled off. The supporting mechanism of the thermal head 5 is provided as much as possible. And by this, attachment can be eliminated easily and reliably. Moreover, the attachment removal operation which moves a thermal head within the movable range of the thermal head 5 by such a support mechanism can be performed only by the forward and reverse rotation operation of the platen roller 4. Therefore, it is not necessary to newly provide a drive source for moving the thermal head, and the attachment removal can be realized at low cost.

(Improvement modification)

(1) In the said embodiment, although the recording paper 2 is conveyed to the upstream side of a reference conveyance direction, and is out of the press position by the platen roller 4, the recording sheet 2 is conveyed to the downstream side of a reference conveyance direction, It is also possible to open the attachment site from pressurization. For example, the thermal head 5 and the rotating shaft may be arranged by reversing the vertical direction in FIG. 1 based on the pressing position of the platen roller 4. By such a structure, attachment can be eliminated by conveyance in a reference conveyance direction. At this time, it is also possible to provide a paper guide member in front of the paper outlet 1b so as to actively exert a force for peeling the recording paper 2 similarly to the paper guide member 6 of the above embodiment.

(2) In the said embodiment, although a reverse conveyance operation and a conveyance operation to a positive direction are performed once, as an attachment removal operation | movement, you may make it perform multiple times of a reverse conveyance operation and a conveyance operation to a positive direction. This makes it possible to more reliably peel off the recording paper 2 attached strongly.

(3) In the said embodiment, although the notch part 10 opened to the conveyance path 3 side is provided, and the guide surface 11 which slides the rotating shaft 13 in the bottom part is provided, the notch part 10 It is also possible to form a long hole or the like that extends in the same direction as the guide surface 11 so as to attach the rotary shaft 13 to the long hole.

(4) In order to ensure the return of the thermal head 5 in step S3 of the said embodiment, the pressing member etc. which tension the thermal head 5 to the upper side (downstream of a reference conveyance direction) are made beforehand. You may provide it.

(5) In the above embodiment, the recording sheet 2 is attached to the thermal head 5 with the heat generating section 8a as the center, but the attachment position (insertion position of the recording sheet 2) is the heating section 8a. It is not limited to the site provided.

(6) Although the above embodiment applies the present invention to the thermal printer 1, it is also applicable to other printers. That is, the present invention is applied to any printer in which the recording medium is likely to adhere to the print head by sandwiching and pressurizing the recording medium between the platen roller and the print head, and being left in this pressurized state during printing standby. can do. The present invention can also be applied to a printer for printing a sheet or a label having a coating layer on the printing surface as a recording medium.

(7) Although the thermal head 5 is tensioned and moved by the conveyance force for conveying the recording sheet 2 in the above embodiment, the thermal head 5 is driven by a drive source different from the conveying means of the recording sheet 2. May be moved out of the contact position with the platen roller 4. In addition, a drive source different from the conveying means of the recording sheet 2 may be a drive source that assists the rotational force of the platen roller 4.

(8) Although the structure of the thermal printer 1 of the said embodiment is described by the head main-body part 8 which contacts the platen roller 4 as the surface parallel to a perpendicular surface, it is not limited to this attitude | position. The head main body 8 may be inclined to the vertical surface to contact the platen roller 4. Also in this case, the recording medium is conveyed by the pressurized region C (the hatching portion described in the head main body 8 in FIG. 3), which is the nip area of the platen roller 4 and the head main body 8. The same effect as the said embodiment can be acquired by arrange | positioning in the same way as arrange | positioning the paper entrance 1a and the paper guide member 7 on the platen roller side rather than the perpendicular surface which passes through the center of a direction. That is, the position of the sheet | seat inlet 1a and the guide member is moved to the platen roller 4 side rather than the imaginary surface containing the tangent of the platen roller 4 which passes through the center of the paper conveyance direction of the to-be-pressed area C. FIG. do. As a result, the recording paper can be wound on the platen roller 4. Furthermore, the guide surface 11 along the rotating shaft 13 formed in the main body of the thermal printer 1 by stretching the guide surface 11 formed on the support frame 9 constituting the support mechanism in a direction away from the virtual surface. In this sliding contact, the support frame 9 moves. By the movement of the support frame 9, the head main body 8 supported by the support frame 9 moves, and the to-be-pressed area C of the head main body 8 shifts to the position where pressurization is released. . At this time, the rotating shaft 13 is arrange | positioned at the head main-body part 8 side with respect to an imaginary surface.

(9) In step S2, the control unit of the thermal printer 1 according to the embodiment executes a control to rotate by a rotation amount corresponding to a reverse transfer of the amount of 24 dots of the printing dot formed by the thermal head 5, and have. Here, the amount of 24 printed dots formed by the thermal head 5 is configured to convey a distance that is sufficiently larger than the movement amount corresponding to the pressurized region C. FIG. Therefore, the present application is not necessarily limited to the above operation. Although the distance L of the paper conveyance direction of the to-be-pressed area | region C of this embodiment changes with the pressure of the head main-body part 8 and the platen roller 4, and the hardness of the platen roller 4, it prints The dot is about 10 to 12 dots.

The configuration of the present application is to prevent the sticking of the recording paper 2 to the thermal head 5. In order to eliminate the attachment by the heat generating section 8a which is the printing section of the thermal head 5, the following operation is performed. When the thermal head 5 is moved to the upstream side in the paper conveying direction to eliminate the distance, the distance L1 from the upstream end in the paper conveying direction of the pressurized region C to the heat generating section 8a (<L) ), The thermal head 5 (that is, the head main body 8) is moved by a distance equal to or greater than. On the other hand, in the case where the thermal head 5 is moved to the downstream side in the paper conveying direction to perform the action, the distance L2 from the downstream end in the paper conveying direction of the pressurized region C to the heat generating portion 8a ( The thermal head 5 (that is, the head main body 8) is moved by a distance of <L) or more. When the heat generating portion 8a is in the center of the pressure-pressed region, L1 = L2 = 1 / 2L. That is, by moving the distance of the paper conveyance direction from the edge part of the to-be-pressed area | region C on the moving direction side of the thermal head 5 to the heat generating part 8a, attachment by the heat generating part 8a is eliminated. Can be.

Moreover, in order to remove the adhesion by the pressurization of the to-be-pressed area | region C, it moves at least the distance L or the distance L of the to-be-pressed area | region C in the paper conveyance direction. Thereby, the pressurization of the recording paper 2 corresponding to the pressurized area C pressed at the time of printing waiting is released, and attachment can be canceled.

(10) In the above embodiment, even when the paper guide member 6 is omitted, the force to peel off acts. This means that when the thermal head 5 moves upstream in the paper conveyance direction, the downstream side of the paper conveyance direction of the recording paper 2 is different from the recording paper at a position corresponding to the pressurized area C. It is supported by the pressing of the part 8 and the platen roller 4. On the other hand, the upstream end of the recording sheet 2 is supported by the roll when the upstream side of the recording sheet 2 is used as the sheet inlet 1a or the recording sheet 2. Since the upstream end of the recording sheet 2 is supported at a position farther from the thermal head 5 than the sheet guide member 6, the force to peel is weakened, but the force to hold and peel acts.

(11) The waiting time T (continuity time of the printing standby state) of the said embodiment is the nip area | region formed by pressurization of the platen roller 4 and the head main-body part 8 (pressurization area | region at the time of printing standby). Is the time from when the recording sheet 2 starts to stop until the print start command accompanying the conveyance operation of the recording sheet 2 is received. As a specific example, it is the time until a printing operation is complete | finished, the platen roller 4 stops in the state which the head main-body part 8 was pressed by the platen roller 4, and then receives a next printing command. This time is measured by a timer (time measuring means) not shown, and the waiting time is obtained from the measured information. When the power is turned off while the platen roller 4 is stopped, in the case where the state where the platen roller 4 and the head main body 8 are being pressed continues, the timer is turned off by the timer. Edo is measured as a waiting time.

(12) In the above embodiment, after the operation of step S2 is completed, the flow advances to step S3, and the recording sheet is conveyed in the forward direction by the same conveyance amount as the opposite conveyance amount of step S2, but is not limited to this operation. For example, when it is avoided to print on the recording paper 2 located in the pressurized area C at the time of printing standby, the distance longer than the opposite conveyance amount can be conveyed. When printing to the entire area of the recording paper 2 located in the to-be-pressed area C is avoided during printing standby, the distance of the opposite conveying amount plus the distance in the paper conveying direction of the to-be-pressed area is shifted.

1: Thermal printer 1a: Paper entrance
1b: paper outlet 2: recording paper (recording medium)
3: conveying path 4: platen roller
5: Thermal head (print head) 6: Paper guide member (guide member)
7: conveying motor 8: head main body
8a: heating portion 9: support frame
10: notch 11: guide surface
12: rotation support surface 13: rotation axis
14: head pressure spring A: forward direction
B: Reference conveyance direction C: Pressurized area
D: bending path E: granular angle
F: Peeling direction P: Insertion position

Claims (8)

A head body portion having a printing portion for printing the recording medium, the head main body portion opposing the platen roller for conveying the recording medium;
A support mechanism for pressing and supporting the head main body portion to the platen roller and moving the head main body portion in a direction of changing the position of contact with the platen roller while pressing the head main body portion to the platen roller. Characterized in that
Print head. The method of claim 1,
Movement of the head body portion in the support mechanism is performed by rotation of the platen roller in a first direction or rotation in a second direction opposite to the first direction.
Print head. The method according to claim 1 or 2,
The support mechanism has a rotation support surface in contact with a rotation axis parallel to the platen roller rotation axis, and a guide surface extending to a position side in contact with the platen roller of the head main body portion in succession to the rotation support surface,
By the contact between the head body portion and the platen roller, the rotation support surface or the guide surface is pressed against the rotation shaft,
The rotation axis moves relatively along the guide surface to move the position contacting the platen roller of the head body portion, and at the same time, rotates the support mechanism on the rotation support surface to contact the platen roller of the head body portion. To move the position
Print head. The method of claim 3, wherein
The guide surface is an inclined surface that is inclined in a direction extending to the back side of the head main body portion toward the rotational support surface side.
Print head. A platen roller for conveying the recording medium,
A print head having a head body portion opposed to the platen roller with a print portion for printing the recording medium;
Pressing means for pressing the print head to the platen roller side;
The head main body is moved in a direction to change the position where the head main body is in contact with the platen roller while the head main body is pressed against the platen roller while supporting the head main body. Characterized in that it has a support mechanism for
printer. The method of claim 5, wherein
Has a conveyance path for conveying the recording medium to a position where the platen roller and the head main body contact;
And a guide member in the conveying path located on the same side as the direction in which the head main body moves relative to the platen roller to guide the recording medium.
printer. Receiving an operation instruction involving the return of the recording medium,
The period of print waiting until the operation instruction is received;
When the measured waiting period of the print exceeds a predetermined period, the head main body is moved in a direction of changing the position where the head main body of the print head contacts the platen roller while being pressed against the platen roller. Characterized by
How to control the printer. The method of claim 7, wherein
The printing standby is in a state where the recording medium is stopped at a position where the head main body portion and the platen roller come into contact with each other.
How to control the printer.

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